Function Blocks
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Function Block Reference Guide
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2.79 WTUN Function Block
Description
The
WTUN
label stands for
Write Tuning Constants.
This block is part of the
Loops
category. It looks
like this graphically on the Control Builder.
Function
Writes the numerical value of Gain, Rate, and Reset to a Target PID, TPSC, or CARB block without any
operator interaction.
Select the target block number from the specific function block diagram and enter it in the appropriate
field in the “Write TuneConstants” dialog box.
• If EN is ON, then the tuning constants are set to the Gain, Rate, and Reset input values..
ATTENTION
Invalid for block number whose type is other than PID, CARB, or TPSC.
If the target block is in AUTO mode, tuning parameter change will cause a bump in the output.
If any input value is “out-of-range”, no values will be written.
Input
GAIN
= Value for GAIN tuning constant
RSET =
Value for RESET tuning constant (Integration time)
RATE =
Value for RATE tuning constant (Derivative time)
EN
= Enable command
ATTENTION
The three analog inputs can originate as recipe items or be calculated for adaptive control.